Micro fuel cell

ABSTRACT

A fuel cell, fuel cell array and methods of forming the same are disclosed. The fuel cell can be made by forming a first aperture defined by a first aperture surface through a first electrode layer and forming a second aperture defined by a second aperture surface through a second electrode layer. A proton exchange membrane is laminated between the first electrode layer and the second electrode layer. At least a portion of the first aperture is at least partially aligned with the second aperture.

This application claims priority to U.S. patent application Ser. No.10/750,581, filed Dec. 29, 2003, entitled “Micro Fuel Cell.”

FIELD OF THE INVENTION

The present invention generally relates to the field of fuel cells, andmore particularly, to micro fuel cells and methods of making the same.

BACKGROUND OF THE INVENTION

A fuel cell produces electrical energy by electrochemically oxidizing afuel such as hydrogen or methanol in the cell to directly convert thechemical energy of the fuel into electrical energy. Fuel cells haverecently drawn attention as a clean supply source for electrical energy.

Powering of portable and/or wireless electronic devices is a significantissue in today's marketplace. While the speed and functionality of manywireless sensors and/or portable telecommunications and computingdevices tend to be limited by the power sources, the availability ofgood power sources is lagging behind development of the electronicdevices themselves. Thus, improved power supply and management isconstantly being sought.

A number of miniature fuel cells suitable for use with electronicproducts are becoming available today, but less attention has been shownto the low-cost mass production and device packaging of these fuel cellsfor varied applications. There is limited information in the literatureconcerning such things as the methods for manufacturing the fuel cellsin a low-cost and efficient manner.

SUMMARY OF THE INVENTION

The present invention generally relates to a fuel cell, fuel cell arrayand methods of forming the same. In one illustrative embodiment, a fuelcell is made by forming a first aperture defined by a first aperturesurface through a first electrode layer and forming a second aperturedefined by a second aperture surface through a second electrode layer. Aproton exchange membrane is then laminated between the first electrodelayer and the second electrode layer, with the proton exchange membranespanning the first aperture and the second aperture. A plurality of fuelcells may also be made in a similar manner, as further described below.

In some embodiments, and to help promote adhesion between the firstelectrode layer, the second electrode layer and the proton exchangemembrane, an adhesive may be provided between the electrode layers andthe proton exchange membrane. Depending on the method of making the fuelcells, the apertures can be formed before or after the adhesive isprovided.

In some embodiments, the first electrode layer and/or the secondelectrode layer may include a conductive substrate, while in otherembodiments, the first electrode layer and/or the second electrode layermay include a non-conductive substrate with a conductive layer appliedto at least a portion thereof. When a conductive layer is applied, theconductive layer may be patterned to form one or more fuel cellelectrical contacts. In some cases, the electrical contacts may extendfrom adjacent the proton exchange membrane near the apertures to aregion that is beyond the extent of the proton exchange membrane. Whensuch electrical contacts are provided on both the first electrode layerand the second electrode layer, at least some of the electrical contactson the first electrode layer may become electrically connected to atleast some of the electrical contacts on the second electrode layer,when the first electrode layer and the second electrode layer arelaminated together. By appropriately patterning the electrical contactson the first and second electrode layers, two or more fuel cells may beelectrically connected in series, in parallel or some combinationthereof to provide the desired electrical output characteristics.

A plurality of fuel cells can be formed by using any number of methodsdisclosed therein. For example, the first electrode layer and the secondelectrode layer may include many apertures, each defining a fuel cell.When a proton exchange membrane is laminated between the first electrodelayer and the second electrode layer, a plurality of fuel cells may bemade. The plurality of fuel cells can then be diced into single fuelcells or fuel cell arrays, as desired. In another illustrativeembodiment, a first length of material having a first pluralityapertures and a first plurality of electrical contacts may be moved witha second length of material having a second plurality apertures and asecond plurality of electrical contacts into a joining unit with aproton exchange membrane therebetween. The second plurality of aperturesare preferably in registration with the first plurality of apertures.Once joined, the resulting plurality of fuel cells can be diced intosingle fuel cells or fuel cell arrays, as desired

BRIEF DESCRIPTION OF THE DRAWINGS

The invention may be more completely understood in consideration of thefollowing detailed description of various embodiments of the inventionin connection with the accompanying drawings, in which:

FIG. 1A-1D are cross-sectional schematic views of an illustrative microfuel cell at various steps of during manufacture;

FIG. 1E is a top schematic view of the micro fuel cell shown in FIG. 1D;

FIG. 2A-2D are cross-sectional schematic views of another illustrativemicro fuel cell at various steps of during manufacture;

FIG. 2E is a top schematic view of the micro fuel cell shown in FIG. 2D;

FIG. 3A-3C are cross-sectional schematic views of another illustrativemicro fuel cell at various steps of during manufacture;

FIG. 3D is a top schematic view of the micro fuel cell shown in FIG. 3C;

FIG. 4A-4C are cross-sectional schematic views of another illustrativemicro fuel cell at various steps of during manufacture;

FIG. 4D is a top schematic view of the micro fuel cell shown in FIG. 4C;

FIG. 5 is a perspective view of an array of micro fuel cells;

FIG. 6 is a perspective view of the array of fuel cells shown in FIG. 5diced into various forms;

FIG. 7 is an exploded perspective view of an array of fuel cells inaccordance with another illustrative embodiment of the invention;

FIG. 8 is a schematic side elevation view of an illustrative method ofmaking the micro fuel cells; and

FIG. 9 is a perspective view of an illustrative fuel cell mounted to afuel reservoir.

While the invention is amenable to various modifications and alternativeforms, specifics thereof have been shown by way of example in thedrawings and will be described in detail. It should be understood,however, that the intention is not to limit the invention to theparticular illustrative embodiments described. On the contrary, theintention is to cover all modifications, equivalents, and alternativesfalling within the spirit and scope of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The following description should be read with reference to the drawings,in which like elements in different drawings are numbered in likefashion. The drawings, which are not necessarily to scale, depictselected embodiments and are not intended to limit the scope of theinvention. Although examples of construction, dimensions, and materialsmay be illustrated for the various elements, those skilled in the artwill recognize that many of the examples provided have suitablealternatives that may be utilized.

The present invention is applicable for use with all devices, and inparticular, those devices that can use small sized power sources. Insome illustrative embodiments, the present invention provides electricalpower using hydrogen and oxygen as a fuel source. While the presentinvention is not so limited, an appreciation of various aspects of theinvention will be gained through a discussion of the variousillustrative embodiments and examples provided below.

FIG. 1A-1D are cross-sectional schematic views of an illustrative microfuel cell at various steps of manufacture. In FIG. 1A, an electrode 110has a top surface 112, a bottom surface 114 and a thickness T₁ definedby the distance between the top surface 112 and the bottom surface 114.In the illustrative embodiment, a substrate 115, which may be anon-conductive substrate, is coated with a conductive material 116 on atleast a portion of the top surface and at least a portion of the bottomsurface 114. The conductive material 116 can have any useful thickness,such as, for example, a thickness of up to 1000 Angstroms or more, asdesired. Optional feed-through contacts 117 are also shown electricallyconnecting the conductive material 116 on the top surface 112 with theconductive material 116 on the bottom surface 114. In an illustrativeembodiment, the electrode 110 can have any useful thickness such as, forexample, a thickness of 2 mil or less. In some embodiments, theconductive material 116 may be patterned to form one or more electricalcontacts or pads. Patterning the conductive material 116 may, forexample, help electrically isolate adjacent fuel cells when a number offuel cells are formed simultaneously.

In FIG. 1B, an optional adhesive layer 120 can be disposed on theelectrode 110. The adhesive layer 120 may be conductive and can bedisposed using conventional methods. The adhesive layer 120 can have anyuseful thickness, and like the conductive material 116 above, may bepatterned in some embodiments, as desired.

In FIG. 1C, an aperture 135 is formed through the electrode 110thickness T₁. The aperture 135 can be formed using conventional methodssuch as, for example, punching, etching, or laser cutting. The aperture135 is defined by an aperture surface 130 surround the aperture 135. Theaperture 135 can be any size or shape. In one illustrative embodiment,the aperture 135 is rectangular, square, or round and has across-sectional surface area of less than 1 mm². However, other shapesand sizes may also be used, as desired. In FIG. 1A-1C, the adhesive 120is shown as being applied before the aperture 135 is formed. However, inother embodiments, the adhesive 120 may be applied after the aperture135 is formed.

FIG. 1D shows a proton exchange membrane 140 laminated between a firstelectrode 110A and a second electrode 110B. The first electrode 110A andthe second electrode 110B can be similar to the electrode 110 describedabove. The proton exchange membrane 140 may be any suitable materialthat allows ions to conduct across it. Forming the proton exchangemembrane encompasses in situ techniques such as spin or solutioncasting, as well as providing a preformed film onto a catalyst. Anillustrative commercially available proton exchange membrane is Nafion®,sold by Dupont (a perfluorosulfuric acid membrane with apolytetrafluoroethylene backbone). Other proton exchange membranes arecommercially available, and are known to those skilled in the art. In apreferred embodiment, the proton exchange membrane can have a thicknessranging from 10 to 50 micrometers. However, other thicknesses may beused, if desired. The proton exchange membrane 140 can further include atop and bottom catalyst layer such as, for example, a carbon/platinumlayer adjacent the proton exchange membrane 140.

In the illustrative embodiment, the adhesive layer 120 is disposedbetween the proton exchange membrane 140 and the first electrode 110A,and between the proton exchange membrane 140 and the second electrode110B. The aperture of the first electrode 110A is aligned with theaperture of the second electrode 110B, thereby forming a fuel cell 100.While perfect alignment between the aperture of the first electrode 110Aand the aperture of the second electrode 110B is not required, theaperture of the first electrode 110A is preferably at least partiallyaligned with the aperture of the second electrode 110B.

The illustrative fuel cell 100 operates as follows. Fuel, e.g., hydrogenor methanol, is introduced into the aperture 135 in the first electrode110A and it diffuses to the first catalyst layer on the proton exchangemembrane 140 first electrode side 110A. The first catalyst layerpromotes removal of electrons (for hydrogen fuel) according to therelationship:

For methanol, the relationship is:

The electrons flow from the first catalyst layer through the conductivematerial 116 on the first electrode 110A and through an external circuit(not shown), while the hydrogen ions (i.e., protons) move across theproton exchange membrane 140 toward the second catalyst layer on theproton exchange membrane 140 second electrode side 110B.

An oxidant, e.g., air or oxygen, is directed into the second electrode110B aperture 135 and diffuses to the second catalyst layer on theproton exchange membrane 140. At this second catalyst layer, oxygen fromthe oxidant reacts both with the hydrogen ions flowing across themembrane 140 and with the electrons flowing to the second catalyst layerfrom the external circuit to form water, according to the relationship:

The electron flow provides the desired current, and the water by-productis removed from the cell, often by evaporation. FIG. 1E is a topschematic view of the illustrative embodiment of a micro fuel cell 100shown in FIG. 1D.

FIG. 2A-2D are cross-sectional schematic views of another illustrativemicro fuel cell at various steps of manufacture. In FIG. 2A, anelectrode 210 has a top surface 212, a bottom surface 214 and athickness T₂ defined by the distance between the top surface 212 and thebottom surface 214. In the illustrative embodiment, the electrode 210 isa conductive material such as, for example, a conductive metal orconductive polymer. In an illustrative embodiment, the electrode 210 canhave any useful thickness such as, for example, a thickness of 2 mil orless. However, other thicknesses may also be used.

In FIG. 2B, an optional adhesive layer 220 can be disposed on theelectrode 210. The adhesive layer 220 may be conductive and can bedisposed using conventional methods. The adhesive layer 220 can have anyuseful thickness.

In FIG. 2C, an aperture 235 can be formed through the electrode 210thickness T₂. The aperture 235 can be formed using conventional methodssuch as, for example, punching, etching, or laser cutting. The aperture235 is defined by an aperture surface 230 surrounding the aperture 235.The aperture 235 can be any useful size or shape. In an illustrativeembodiment, the aperture 235 is rectangular, square, or round and has across-sectional surface area of less than 1 mm². In FIG. 2A-2C, theadhesive 220 is shown as being applied before the aperture 235 isformed. However, in other embodiments, the adhesive 220 may be appliedafter the aperture 235 is formed.

FIG. 2D shows a proton exchange membrane 240 laminated between a firstelectrode 210A and a second electrode 210B. The first electrode 210A andthe second electrode 210B can be similar to the electrode 210 describedabove. In the illustrative embodiment, the adhesive layer 220 isdisposed between the proton exchange membrane 240 and the firstelectrode 210A, and between the proton exchange membrane 240 and thesecond electrode 210B. Like above, the aperture of the first electrode210A is at least partially aligned with the aperture of the secondelectrode 210B. The completed assembly forms a fuel cell 200. The protonexchange membrane 240 can further include a top and bottom catalystlayer adjacent the proton exchange membrane 240, as described above.FIG. 2E is a top schematic view of the illustrative embodiment of amicro fuel cell 200 shown in FIG. 2D.

FIG. 3A-3D are cross-sectional schematic views of another illustrativemicro fuel cell at various steps during manufacture. In FIG. 3A, anelectrode 310 has a top surface 312, a bottom surface 314 and athickness T₃ defined by the distance between the top surface 312 and thebottom surface 314. In the illustrative embodiment, the electrode 310 isa conductive material such as, for example, a conductive metal orconductive polymer. In an illustrative embodiment, the electrode 310 canhave any useful thickness such as, for example, a thickness of 2 mil orless.

In the illustrative embodiment, an aperture 335 can be pre-formedthrough the electrode 310 thickness T₃. The aperture 335 can be formedusing conventional methods such as, for example, punching, etching, orlaser cutting. The aperture 335 is defined by an aperture surface 330surrounding the aperture 335. The aperture 335 can be any useful size orshape. In an illustrative embodiment, the aperture 335 is rectangular,square, or round and has a cross-sectional surface area of less than 1mm².

In FIG. 3B, an optional adhesive layer 320 can be disposed on theelectrode 310. The adhesive layer 320 may be conductive and may bedisposed using conventional methods. The adhesive layer 320 can have anyuseful thickness. In FIG. 3A-3C, the adhesive 320 is shown as beingapplied after the aperture 335 is formed. However, in other embodiments,the adhesive 320 may be applied before the aperture 335 is formed.

FIG. 3C shows a proton exchange membrane 340 laminated between a firstelectrode 310A and a second electrode 310B. The first electrode 310A andthe second electrode 310B can be similar to the electrode 310 describedabove. In the illustrative embodiment, the adhesive layer 320 isdisposed between the proton exchange membrane 340 and the firstelectrode 310A, and between the proton exchange membrane 340 and thesecond electrode 310B. The aperture of the first electrode 310A is atleast partially aligned with the aperture of the second electrode 310B.The completed assembly forms a fuel cell 300. The proton exchangemembrane 340 can further include a top and bottom catalyst layeradjacent the proton exchange membrane 340, as described above. FIG. 3Dis a top schematic view of the illustrative embodiment of a micro fuelcell 300 shown in FIG. 3C.

FIG. 4A-4D are cross-sectional schematic views of another illustrativemicro fuel cell at various steps of during manufacture. In FIG. 4A, anelectrode 410 has a top surface 412, a bottom surface 414 and athickness T₄ defined by the distance between the top surface 412 and thebottom surface 414. In the illustrative embodiment, the electrode 410includes a non-conductive material or substrate 415. In an illustrativeembodiment, the electrode 410 can have any useful thickness such as, forexample, a thickness of 2 mil or less.

In the illustrative embodiment, an aperture 435 is pre-formed throughthe electrode 410 thickness T₄. The aperture 435 can be formed usingconventional methods such as, for example, punching, etching, or lasercutting. The aperture 435 is defined by an aperture surface 430surrounding the aperture 435. The aperture 435 can be any useful size orshape. In an illustrative embodiment, the aperture 435 is rectangular,square, or round and has a cross-sectional surface area of less than 1mm².

In the illustrative embodiment of FIG. 4A, the substrate 415 is coatedwith a conductive material 416 on at least a portion of, or the entireaperture surface 430. In addition, the conductive material can bedisposed on at least a portion of the top surface 412 and/or at least aportion of the bottom surface 414. In some embodiments, the conductivematerial may be patterned on the top surface 412 and/or the bottomsurface 414. The conductive material 116 on the aperture surface 430 mayprovide a seal that helps prevent the fuel from escaping from theaperture 435, particularly if the substrate 415 is somewhat porous tothe fuel source. In an illustrative embodiment, the conductive material116 can have any useful thickness, such as, for example, a thickness ofup to 1000 Angstroms. The conductive material 116 can be a conductivemetal or conductive polymer, for example.

In FIG. 4B an optional adhesive layer 420 can be disposed on theelectrode 410. The adhesive layer 420 may be conductive and can bedisposed using conventional methods. The adhesive layer 420 can have anyuseful thickness. In some cases, the aperture is formed after theadhesive is applied, while in others it is formed before the adhesive isapplied.

FIG. 4C shows a proton exchange membrane 440 laminated between a firstelectrode 410A and a second electrode 410B. The first electrode 410A andthe second electrode 410B can be similar to the electrode 410 describedabove. In the illustrative embodiment, the adhesive layer 420 isdisposed between the proton exchange membrane 440 and the firstelectrode 410A, and between the proton exchange membrane 440 and thesecond electrode 410B. Like above, the aperture of the first electrode410A is at least partially aligned with the aperture of the secondelectrode 410B. The completed assembly forms a fuel cell 400. The protonexchange membrane 440 can further include a top and bottom catalystlayer adjacent the proton exchange membrane 440, as described above.FIG. 4D is a top schematic view of the illustrative embodiment of amicro fuel cell 400 shown in FIG. 4C.

FIG. 5 is a perspective view of an array of micro fuel cells. In someillustrative embodiments, a plurality of micro fuel cells 500 can beeconomically produced on a large sheet 501 of material. The sheet 510can include a plurality of apertures 535 through a top electrode 510Aand a bottom electrode 510B, as described above. Each aperture has anaperture cross-sectional surface area 530, as described above. A protonexchange membrane 540 can be disposed between the top electrode 510A andthe bottom electrode 510B, preferably spanning the apertures so as tobecome exposed to a fuel source.

FIG. 6 is a perspective view of an array of fuel cells 600 shown in FIG.5, diced into various forms. The sheet 501 of FIG. 5 can be divided intosingle fuel cells, or a plurality of fuel cell arrays. In some cases,the fuel cells in a fuel cell array can be connected in series, inparallel, or some combination thereof, depending on the application.Connecting the fuels cells in series will tend to increase the outputvoltage level, while connecting the fuel cells in parallel with tend toincrease the output current level. Thus, by appropriately connecting thefuel cells in parallel and/or series, desired electrical outputcharacteristics of the fuel cell can be achieved. In one illustrativeembodiment, each fuel cell array can have five or more fuel cellselectrically connected in series.

FIG. 7 is an exploded perspective view of an array of fuel cells 700 inaccordance with an illustrative embodiment of the invention. In theillustrative embodiment, a top electrode 710A has a plurality ofapertures 735A and a bottom electrode 710B has a plurality of apertures735B. The apertures 735A and 735B are shown at least partially alignedwith a proton exchange membrane 740 disposed between the top electrode710A and the bottom electrode 710B. The proton exchange membrane 740 isshown spanning the apertures 735A and 735B and extending along a protonexchange membrane (PEM) region 745A and 745B.

Electrical contacts 750A extend away from the apertures 735A on the topelectrode 710A to a first region 755A. Electrical contacts 750B extendaway from the apertures 735B on the bottom electrode 710B to a firstregion 755B. At least one electrical contact 750A on the top electrode710A at least partially overlaps an electrical contact 750B on thebottom electrode 710B in an overlap region 760A and 760B. In theillustrative embodiment, the proton exchange membrane 740 does notextend out between the top electrode 710A or bottom electrode 710B inthe overlap region 760A and 760B. Thus, when the top electrode 710A islaminated to the bottom electrode, with the proton exchange membrane 740disposed therebetween, the electrical contact 750A on the top electrode710A may become electrically connected to the electrical contact 750B onthe bottom electrode 710B. This may electrically connect one micro fuelcell in series with another micro fuel cell. Similar methods may be usedto electrically connect micro fuel cells in parallel, and/or in seriesand in parallel, as desired.

FIG. 8 is a schematic side elevation view of an illustrative method ofmaking the micro fuel cells. In the illustrative embodiment, an array offuel cells 800 can be formed on a continuous sheet at shown in FIG. 5 ina roll to roll process. A continuous length of top electrode 710A can beprovided on a first roll 705A. For example, a continuous length ofbottom electrode 710B can be provided on a second roll 705B. Thecontinuous length of top electrode 710A and bottom electrode 710B can besimultaneous moved into a joining unit 880 with a continuous length ofproton exchange membrane 840 between the continuous length of topelectrode 710A and bottom electrode 710B. Apertures can be pre-formed orformed just prior to entering the joining unit 880. The apertures in thetop electrode 710A and bottom electrode 710B are in at least partialregistration prior to entering the joining unit 880. The joining unit880 can be any conventional laminating operation that applies pressureto the top electrode 810A and bottom electrode 810B to form a fuel celllaminate described herein. When an adhesive is to be used, the adhesivecan be applied to the proton exchange membrane and/or the top electrode710A and bottom electrode 710B prior to entering the joining unit 880.After exiting the joining unit 880, a dicer may be provided for dicingthe plurality of fuel cells into single fuel cells or fuel cell arrays,if desired.

FIG. 9 is a perspective view of an illustrative fuel cell 900 mounted toa fuel reservoir 909. In the illustrative embodiment, a fuel cell array900 is fixed to the reservoir 909 such that the proton exchange membraneis exposed through the apertures to the fuel in the reservoir 909. Thereservoir 909 can contain a fuel source such as hydrogen or the like.The fuel cell array 900 may include electrical contacts 912A and 912B,which may represent two or more fuel cells connected in series, parallelor some combination thereof. The electrical contacts 912A and 912B maybe used to provide power to an external load. In this embodiment, thebyproduct is water, which collects on the outer surface of the protonexchange membrane, and evaporates into the surrounding air.

The present invention should not be considered limited to the particularexamples described above, but rather should be understood to cover allaspects of the invention as fairly set out in the attached claims.Various modifications, equivalent processes, as well as numerousstructures to which the present invention can be applicable will bereadily apparent to those of skill in the art to which the presentinvention is directed upon review of the instant specification.

1. A method of forming a fuel cell, comprising the steps of: providing afirst substrate with a first aperture extending through the firstsubstrate; providing a second substrate with a second aperture extendingthrough the second substrate; laminating a proton exchange membranebetween the first substrate and the second substrate where the firstaperture is at least partially aligned with the second aperture.
 2. Amethod according to claim 1 wherein the proton exchange membraneincludes a catalyst.
 3. A method according to claim 1, wherein an innersurface of the first substrate facing the proton exchange membraneextends beyond the proton exchange membrane in at least one region, andan inner surface of the second substrate facing the proton exchangemembrane extends beyond the proton exchange membrane in the at least oneregion.
 4. A method according to claim 3 further comprising the step ofproviding an adhesive between the inner surface of the first substrateand the inner surface of the second substrate in the at least oneregion.
 5. A method according to claim 1 further comprising the stepsof: providing a first conductive layer on an inner surface of the firstsubstrate facing the proton exchange membrane adjacent to the firstaperture; and providing a second conductive layer on an inner surface ofthe second substrate facing the proton exchange membrane adjacent to thesecond aperture.
 6. A method according to claim 5 wherein the innersurface of the first substrate extends beyond the proton exchangemembrane in at least one interconnect region, and the inner surface ofthe second substrate extends beyond the proton exchange membrane in theat least one interconnect region.
 7. A method according to claim 6wherein the first conductive layer extends into the at least oneinterconnect region and the second conductive layer extends into the atleast one interconnect region and overlaps and makes an electricalconnection to the first conductive layer.
 8. A method according to claim7, wherein the first substrate and the second substrate aresubstantially non-conductive.
 9. A method of forming a plurality of fuelcells, comprising the steps of: forming a first plurality of aperturesthrough a first sheet; forming a second plurality of apertures through asecond sheet; and laminating a proton exchange membrane between thefirst sheet and the second sheet, where the first plurality of aperturesare at least partially aligned with the second plurality of apertures.10. A method according to claim 9 wherein the proton exchange membraneincludes a catalyst.
 11. A method according to claim 10 wherein theproton exchange membrane includes a perfluorosulfuric acid membrane witha polytetrafluoroethylene backbone.
 12. A method according to claim 11wherein the catalyst includes carbon/platinum.
 13. A method according toclaim 9, wherein an inner surface of the first sheet facing the protonexchange membrane extends beyond the proton exchange membrane in atleast one region, and an inner surface of the second sheet facing theproton exchange membrane extends beyond the proton exchange membrane inthe at least one region.
 14. A method according to claim 13 furthercomprising the step of providing an adhesive between the inner surfaceof the first sheet and the inner surface of the second sheet in the atleast one region.
 15. A method according to claim 9 further comprisingthe steps of: providing two or more first conductive electrodes on aninner surface of the first sheet facing the proton exchange membraneadjacent to at least two of the first plurality of apertures; andproviding two or more second conductive electrodes on an inner surfaceof the second sheet facing the proton exchange membrane adjacent to atleast two of the second plurality of apertures.
 16. A method accordingto claim 15 wherein the inner surface of the first sheet extends beyondthe proton exchange membrane in at least one interconnect region, andthe inner surface of the second substrate extends beyond the protonexchange membrane in the at least one interconnect region.
 17. A methodaccording to claim 16 wherein at least one of the first conductiveelectrodes extends into the at least one interconnect region and atleast one of the second conductive electrodes extends into the at leastone interconnect region and overlaps and makes an electrical connectionto the at least one first conductive electrodes.
 18. A method accordingto claim 17, wherein the first sheet and the second sheet aresubstantially non-conductive.
 19. A fuel cell comprising: a firstsubstrate having a first aperture; a second substrate having a secondaperture; and a proton exchange membrane disposed between the firstsubstrate and the second substrate and spanning the first aperture andthe second aperture; wherein, the first aperture is at least partiallyaligned with the second aperture and the proton exchange layer isunsupported across at least a major portion of the first aperture andthe second aperture.
 20. The fuel cell according to claim 19, whereinthe proton exchange membrane has a thickness of 1 mil or less.
 21. Thefuel cell according to claim 20, wherein at least one of the firstaperture and the second aperture has a cross-sectional area of 1 mm² orless.
 22. The fuel cell according to claim 20, wherein the alignedportion of the first aperture and the second aperture has across-sectional area of 1 mm² or less.
 23. The fuel cell according toclaim 19, wherein the first sheet has a thickness of 2 mil or less. 24.The fuel cell according to claim 23, wherein the second sheet has athickness of 2 mil or less.
 25. The fuel cell according to claim 19further comprising a first electrode on an inner surface of the firstsheet facing the proton exchange membrane.
 26. The fuel cell accordingto claim 25 wherein the first electrode extends adjacent to the firstaperture.
 27. The fuel cell according to claim 15 further comprising asecond electrode on an inner surface of the second sheet facing theproton exchange membrane.
 28. The fuel cell according to claim 27wherein the second electrode extends adjacent to the second aperture.29. A fuel cell according to claim 28 wherein the inner surface of thefirst sheet extends beyond the proton exchange membrane in at least oneinterconnect region, and the inner surface of the second sheet extendsbeyond the proton exchange membrane in the at least one interconnectregion, and wherein the first electrode extends into the at least oneinterconnect region and the second electrode extends into the at leastone interconnect region and makes an electrical connection to the firstelectrode.
 30. A fuel cell, comprising: a top layer having a firstplurality of electrical contacts and a first plurality of apertureswhere at least selected first electrical contacts extend from adjacentcorresponding apertures to a first region; a bottom layer having asecond plurality of electrical contacts and a second plurality ofapertures wherein where at least selected second electrical contactsextend from adjacent corresponding apertures to a second region, whereinthe first region at least partially overlaps the second region in anoverlap region; and a proton exchange membrane disposed between the toplayer and bottom layer adjacent the apertures but not in the overlapregion.
 31. The fuel cell according to claim 30, wherein an adhesivelayer is disposed between the top layer and the bottom layer in theoverlap region.
 32. A method of forming a plurality of fuel cells,comprising the steps of: providing a first length of material having afirst plurality apertures and a first plurality of electrical contacts;providing a second length of material having a second pluralityapertures and a second plurality of electrical contacts; providing aproton exchange membrane; moving the first length of material into ajoining unit; moving the second length of material into the joining unitsuch that the second plurality of apertures are at least partially inregistration with the first plurality of apertures; and moving theproton exchange membrane into the joining unit simultaneously with andin between the first and second length of material, at least part of theproton exchange membrane aligned with the plurality of first and secondapertures to form a plurality of fuel cells.
 33. A method according toclaim 32, wherein an inner surface of the first length of materialextends beyond the proton exchange membrane in at least one region, andan inner surface of the second length of material extends beyond theproton exchange membrane in the at least one region.
 34. A methodaccording to claim 33 further comprising the step of providing anadhesive between the inner surface of the first length of material andthe inner surface of the second length of material in the at least oneregion.
 35. A method according to claim 32, further comprising the stepof dicing the plurality of fuel cells into arrays of fuel cells.
 36. Amethod of forming a fuel cell, comprising the steps of: providing afirst substrate having an inside surface and an outside surface and afirst aperture extending from the inside surface to the outside surface;providing a first electrode layer adjacent the first aperture on theinside surface of the first substrate; providing a second substratehaving an inside surface and an outside surface and a second apertureextending from the inside surface to the outside surface; providing asecond electrode layer adjacent the second aperture on the insidesurface of the second substrate; and sandwiching a proton exchangemembrane between the inside surface of the first substrate and theinside surface of the second substrate, where the first aperture is atleast partially aligned with the second aperture with the protonexchange membrane extending therebetween.
 37. A method according toclaim 36 wherein the proton exchange membrane includes a catalyst.
 38. Amethod according to claim 36 wherein the inner surface of the firstsubstrate extends beyond the proton exchange membrane in at least oneregion, and the inner surface of the second substrate extends beyond theproton exchange membrane in the at least one region.
 39. A methodaccording to claim 38 further comprising the step of providing anadhesive between the inner surface of the first substrate and the innersurface of the second substrate in the at least one region.
 40. A methodaccording to claim 36 wherein the inner surface of the first substrateextends beyond the proton exchange membrane in at least one interconnectregion, and the inner surface of the second substrate extends beyond theproton exchange membrane in the at least one interconnect region.
 41. Amethod according to claim 40 wherein the first electrode layer extendsinto the at least one interconnect region and the second electrode layerextends into the at least one interconnect region and makes anelectrical connection to the first electrode layer.